//截取中英文的字符串,中英文都算一个字符 //举个例子： //var length = "你爹临睡前123".subbytestr(0, 5); //alert(length);//输出：你爹临睡前 String.prototype.subbytestr = function (a, b) { var d = this; var e = 0; var f = 0; if (this.length > a && d.length > b) { for (var i = a; i < b; i++) { var c = d.charCodeAt(i); if (c >= 0x4E00 && c <= 0x9FA5) { f++ } else { e++ } } b = (b - a) * 2; if (f) { b -= (e + f) } d = d.substring(a, b) } return d.toString() };/** * 可变长字符串，相比较加号更节省内存空间，对于大量字符串拼接时建议使用。 * 示：{@code * var html = new StringBuilder(); * html.append('<li></li>'); * html.toString(); * } * @constructor */function StringBuilder() { this._strings = [];}StringBuilder.prototype.append = function (val) { this._strings.push(val);}StringBuilder.prototype.clear = function () { this._strings.length = 0;}StringBuilder.prototype.toString = function () { return this._strings.join('');}/** * 日期格式化 * @param date 日期 * @param mask 格式化字符串 * @param utc 是否采用UTC世界时间 * @return {String} */Date.format = function (date, mask, utc) { var token = /w{1}|d{1,4}|m{1,4}|yy(?:yy)?|([HhMsTt])\1?|[LloSZ]|"[^"]*"|'[^']*'/g, timezone = /\b(?:[PMCEA][SDP]T|(?:Pacific|Mountain|Central|Eastern|Atlantic) (?:Standard|Daylight|Prevailing) Time|(?:GMT|UTC)(?:[-+]\d{4})?)\b/g, timezoneClip = /[^-+\dA-Z]/g, pad = function (val, len) { val = String(val); len = len || 2; while (val.length < len) { val = "0" + val; } return val; }, // Some common format strings masks = { "default": "yyyy-mm-dd", shortDate: "m/d/yy", //mediumDate: "mmm d, yyyy", longDate: "mmmm d, yyyy", fullDate: "dddd, mmmm d, yyyy", shortTime: "h:MM TT", //mediumTime: "h:MM:ss TT", longTime: "h:MM:ss TT Z", isoDate: "yyyy-mm-dd", isoTime: "HH:MM:ss", isoDateTime: "yyyy-mm-dd'T'HH:MM:ss", isoUTCDateTime: "UTC:yyyy-mm-dd'T'HH:MM:ss'Z'", //added by jayli localShortDate: "yy年mm月dd日", localShortDateTime: "yy年mm月dd日 hh:MM:ss TT", localLongDate: "yyyy年mm月dd日", localLongDateTime: "yyyy年mm月dd日 hh:MM:ss TT", localFullDate: "yyyy年mm月dd日 w", localFullDateTime: "yyyy年mm月dd日 w hh:MM:ss TT" }, // Internationalization strings i18n = { dayNames: [ "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", //"星期日","星期一","星期二","星期三","星期四","星期五","星期六", "周日", "周一", "周二", "周三", "周四", "周五", "周六" ], monthNames: [ "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec", "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" ] }; // You can't provide utc if you skip other args (use the "UTC:" mask prefix) if (arguments.length == 1 && Object.prototype.toString.call(date) == "[object String]" && !/\d/.test(date)) { mask = date; date = undefined; } // Passing date through Date applies Date.parse, if necessary date = date ? new Date(date) : new Date(); if (isNaN(date)) { throw SyntaxError("invalid date"); } mask = String(masks[mask] || mask || masks["default"]); // Allow setting the utc argument via the mask if (mask.slice(0, 4) == "UTC:") { mask = mask.slice(4); utc = true; } var _ = utc ? "getUTC" : "get",d = date[_ + "Date"](),D = date[_ + "Day"](),m = date[_ + "Month"](),y = date[_ + "FullYear"](),H = date[_ + "Hours"](),M = date[_ + "Minutes"](),s = date[_ + "Seconds"](),L = date[_ + "Milliseconds"](),o = utc ? 0 : date.getTimezoneOffset(),flags = { d: d, dd: pad(d), ddd: i18n.dayNames[D], dddd: i18n.dayNames[D + 7], w: i18n.dayNames[D + 14], m: m + 1, mm: pad(m + 1), mmm: i18n.monthNames[m], mmmm: i18n.monthNames[m + 12], yy: String(y).slice(2), yyyy: y, h: H % 12 || 12, hh: pad(H % 12 || 12), H: H, HH: pad(H), M: M, MM: pad(M), s: s, ss: pad(s), l: pad(L, 3), L: pad(L > 99 ? Math.round(L / 10) : L), t: H < 12 ? "a" : "p", tt: H < 12 ? "am" : "pm", T: H < 12 ? "A" : "P", TT: H < 12 ? "AM" : "PM", Z: utc ? "UTC" : (String(date).match(timezone) || [""]).pop().replace(timezoneClip, ""), o: (o > 0 ? "-" : "+") + pad(Math.floor(Math.abs(o) / 60) * 100 + Math.abs(o) % 60, 4), S: ["th", "st", "nd", "rd"][d % 10 > 3 ? 0 : (d % 100 - d % 10 != 10) * d % 10]}; return mask.replace(token, function ($0) { return $0 in flags ? flags[$0] : $0.slice(1, $0.length - 1); });}/** * 将字符串转换成日期 * @return {*} 转换失败会返回null */Date.parseDate = function () { var date = null; if (!(date instanceof Date)) { date = new Date(data.replace(/-/g, '/')); } else { return date; } // Validate if (date instanceof Date && (date != "Invalid Date") && !isNaN(date)) { return date; } else { return null; }}//计算字符串长度，中文为2，英文为1，中文标点为1String.prototype.bytelength = function() { var a = 0; for (var i = 0; i < this.length; i++) { if (this.charCodeAt(i) >= 0x4E00 && this.charCodeAt(i) <= 0x9FA5) { a += 2 } else { a += 1 } } return a};/** * 格式化字符串，形同C#的String.Format，示：{@code '<li>{0}</li>'.format('结算中');} * @return {String} */String.prototype.format = function() { var args = arguments; return this.replace(/\{(\d+)\}/g, function(m, i) { return args[i]; });}};
